Molecular Epidemiology of Rhinovirus/Enterovirus and Their Role on Cause Severe and Prolonged Infection in Hospitalized Patients

Rhinovirus is one of the most common respiratory viruses, causing both upper and lower respiratory tract infections. It affects mainly children and could cause prolonged infections, especially in immunocompromised patients. Here we report our data on a 15-month surveillance of Rhinovirus seasonality and circulation in Lombardy Region, Italy. All rhinovirus/enterovirus-positive samples were amplified with RT-PCR for the VP4-VP2 region to assign the correct genotype. The median age of RV/EV-positive patients is 9 years, with a range of 0-96. RV-A and RV-C were detected in the majority of cases, while RV-B accounted for less than 10% of cases. An enterovirus species was detected in 6.45% of the cases. A total of 7% of the patients included in this study had a prolonged infection with a median duration of 62 days. All these patients were immunocompromised and most of them were pediatric with an RV-A infection. Two outbreaks were identified, mainly in the neonatal intensive care unit (NICU) and Oncohematology Department, caused by RV A89 and C43, respectively. Nearly 4.5% of the patients were admitted to the ICU requiring mechanical ventilation; all of which had preexisting comorbidities.